Cosmid Cloning of Five \u3cem\u3eZymomonas trp\u3c/em\u3e Genes by Complementation of \u3cem\u3eEscherichia coli\u3c/em\u3e and \u3cem\u3ePseudomonas putida trp\u3c/em\u3e Mutants

A library of Zymomonas mobilis genomic DNA was constructed in the broad-host-range cosmid pLAFR1. The library was mobilized into a variety of Escherichia coli and Pseudomonas putida trp mutants by using the helper plasmid pRK2013. Five Z. mobilis trp genes were identified by the ability to complement the trp mutants. The trpF, trpB, and trpA genes were on one cosmid, while the trpD and trpC genes were on two separate cosmids. The organization of the Z. mobilis trp genes seems to be similar to the organization found in Rhizobium spp., Acinetobacter calcoaceticus, and Pseudomonas acidovorans. The trpF, trpB, and trpA genes appeared to be linked, but they were not closely associated with trpD or trpC genes

Nodule Initiation Elicited by Noninfective Mutants of \u3cem\u3eRhizobium phaseoli\u3c/em\u3e

Rhizobium phaseoli CE106, CE110, and CE115, originally derived by transposon mutagenesis (Noel et al., J. Bacteriol. 158:149-155, 1984), induced the formation of uninfected root nodule-like swellings on bean (Phaseolus vulgaris). Bacteria densely colonized the root surface, and root hair curling and initiation of root cortical-cell divisions occurred normally in mutant-inoculated seedlings, although no infection threads formed. The nodules were ineffective, lacked leghemoglobin, and were anatomically distinct from normal nodules. Ultrastructural specialization for ureide synthesis, characteristic of legumes that form determinate nodules, was absent. Colony morphology of the mutant strains on agar plates was less mucoid than that of the wild type, and under some cultural conditions, the mutants did not react with Cellufluor, a fluorescent stain for β-linked polysaccharide. These observations suggest that the genetic lesions in these mutants may be related to extracellular polysaccharide synthesis

Does the Sun Shrink with Increasing Magnetic Activity?

We have analyzed the full set of SOHO/MDI f- and p-mode oscillation frequencies from 1996 to date in a search for evidence of solar radius evolution during the rising phase of the current activity cycle. Like Antia et al. (2000), we find that a significant fraction of the f-mode frequency changes scale with frequency; and that if these are interpreted in terms of a radius change, it implies a shrinking sun. Our inferred rate of shrinkage is about 1.5 km/y, which is somewhat smaller than found by Antia et al. We argue that this rate does not refer to the surface, but rather to a layer extending roughly from 4 to 8 Mm beneath the visible surface. The rate of shrinking may be accounted for by an increasing radial component of the rms random magnetic field at a rate that depends on its radial distribution. If it were uniform, the required field would be ~7 kG. However, if it were inwardly increasing, then a 1 kG field at 8 Mm would suffice. To assess contribution to the solar radius change arising above 4Mm, we analyzed the p-mode data. The evolution of the p-mode frequencies may be explained by a magnetic^M field growing with activity. The implications of the near-surface magnetic field changes depend on the anisotropy of the random magnetic field. If the field change is predominantly radial, then we infer an additional shrinking at a rate between 1.1-1.3 km/y at the photosphere. If on the other hand the increase is isotropic, we find a competing expansion at a rate of 2.3 km/y. In any case, variations in the sun's radius in the activity cycle are at the level of 10^{-5} or less, hence have a negligible contribution to the irradiance variations.Comment: 10 pages (ApJ preprint style), 4 figures; accepted for publication in Ap

Fine-Structure Map of the Histidine Transport Genes in \u3cem\u3eSalmonella typhimurium\u3c/em\u3e

Afine-structure genetic map of the histidine transport region of the Salmonella typhimurium chromosome was constructed. Twenty-five deletion mutants were isolated and used for dividing the hisJ and hisP genes into 8 and 13 regions respectively. A total of 308 mutations, spontaneous and mutagen induced, have been placed in these regions by deletion mapping. The histidine transport operon is presumed to be constituted of genes dhuA, hisJ, and hisP, and the regulation of the hosP and hisJ genes by dhuA is discussed. The orientation of this operon relative to purF has been established by three-point crosses as being: purF duhA hisJ hisP

Spatial Fay-Herriot Models for Small Area Estimation with Functional Covariates

The Fay-Herriot (FH) model is widely used in small area estimation and uses auxiliary information to reduce estimation variance at undersampled locations. We extend the type of covariate information used in the FH model to include functional covariates, such as social-media search loads or remote-sensing images (e.g., in crop-yield surveys). The inclusion of these functional covariates is facilitated through a two-stage dimension-reduction approach that includes a Karhunen-Lo\`{e}ve expansion followed by stochastic search variable selection. Additionally, the importance of modeling spatial autocorrelation has recently been recognized in the FH model; our model utilizes the intrinsic conditional autoregressive class of spatial models in addition to functional covariates. We demonstrate the effectiveness of our approach through simulation and analysis of data from the American Community Survey. We use Google Trends searches over time as functional covariates to analyze relative changes in rates of percent household Spanish-speaking in the eastern half of the United States.Comment: 26 pages, 5 figure

Pseudo-ataxia due to Osteoid Osteoma

Background: Ataxia is diagnosed by typical features on examination suggestive of a cerebellar etiology and can invoke extensive diagnostic testing. Osteoid osteomas (OOs) are benign bone tumors of the lower limbs that occasionally present with focal neurological signs. Case Report: A 3-year-old male presented with apparent progressive gait ataxia and non-specific leg pain. Initial imaging was unremarkable. However, 12 months later, a lesion was identified in the distal right femur, which was found to be an OO. The gait disorder and pain resolved after surgery. Discussion: This case highlights the challenges of diagnosing a gait disorder in young children

Effects of sorghum wet distillers grains plus solubles in steam-flaked corn–based finishing diets on steer performance, carcass characteristics, and digestibility characteristics

Two studies were conducted to evaluate the effects of sorghum wet distillers grains (SWDGS) in finishing diets on steer performance, carcass characteristics, and nutrient digestibility. In Exp. 1, 240 steers (initial BW = 379 ± 1 kg) were fed steam-flaked corn–based diets with or without 25% SWDGS and 7.5, 10.0, or 12.5% alfalfa hay. There were no effects of alfalfa hay concentration on BW, DMI, ADG, or G:F (P ≥ 0.16). Including SWDGS reduced (P ≤ 0.05) ADG and G:F. Fat thickness decreased (P = 0.03) and DP tended to decrease (P = 0.09) linearly as level of alfalfa hay increased. Final BW of steers consuming diets containing 25% SWDGS were 12 kg lighter (P = 0.05) than those of steers fed diets without SWDGS. Hot carcass weight tended (P = 0.09) to be lighter for steers fed SWDGS. In Exp. 2, effects of corn processing method (steam-flaked corn and dry-rolled corn) and 20% corn wet distillers grains with solubles (CWDGS) or SWDGS inclusion on ruminal pH and in situ digestibility were evaluated. Cattle consuming diets containing SWDGS had a greater (P ≤ 0.05) ruminal pH than steers consuming diets with CWDGS or no wet distillers grains with solubles. Including wet distillers grains with solubles did not affect (P ≥ 0.37) steam-flaked corn or dry-rolled corn in situ DM digestibility. In situ digestibility of DM and NDF differed between CWDGS and SWDGS (P \u3c 0.0001). Differences in performance and nutrient digestibility between CWDGS and SWDGS are the result of differences in the product rather than an interaction with corn processing method

Quantum entanglement between electronic and vibrational degrees of freedom in molecules

We consider the quantum entanglement of the electronic and vibrational degrees of freedom in molecules with a tendency towards double welled potentials using model coupled harmonic diabatic potential-energy surfaces. The von Neumann entropy of the reduced density matrix is used to quantify the electron-vibration entanglement for the lowest two vibronic wavefunctions in such a bipartite system. Significant entanglement is found only in the region in which the ground vibronic state contains a density profile that is bimodal (i.e., contains two separate local minima). However, in this region two distinct types of entanglement are found: (1) entanglement that arises purely from the degeneracy of energy levels in the two potential wells and which is destroyed by slight asymmetry, and (2) entanglement that involves strongly interacting states in each well that is relatively insensitive to asymmetry. These two distinct regions are termed fragile degeneracy-induced entanglement and persistent entanglement, respectively. Six classic molecular systems describable by two diabatic states are considered: ammonia, benzene, semibullvalene, pyridine excited triplet states, the Creutz-Taube ion, and the radical cation of the "special pair" of chlorophylls involved in photosynthesis. These chemically diverse systems are all treated using the same general formalism and the nature of the entanglement that they embody is elucidated

Corpuscular model of two-beam interference and double-slit experiments with single photons

We introduce an event-based corpuscular simulation model that reproduces the wave mechanical results of single-photon double slit and two-beam interference experiments and (of a one-to-one copy of an experimental realization) of a single-photon interference experiment with a Fresnel biprism. The simulation comprises models that capture the essential features of the apparatuses used in the experiment, including the single-photon detectors recording individual detector clicks. We demonstrate that incorporating in the detector model, simple and minimalistic processes mimicking the memory and threshold behavior of single-photon detectors is sufficient to produce multipath interference patterns. These multipath interference patterns are built up by individual particles taking one single path to the detector where they arrive one-by-one. The particles in our model are not corpuscular in the standard, classical physics sense in that they are information carriers that exchange information with the apparatuses of the experimental set-up. The interference pattern is the final, collective outcome of the information exchanges of many particles with these apparatuses. The interference patterns are produced without making reference to the solution of a wave equation and without introducing signalling or non-local interactions between the particles or between different detection points on the detector screen.Comment: Accepted for publication in J. Phys. Soc. Jpn

Discerning Aggregation in Homogeneous Ensembles: A General Description of Photon Counting Spectroscopy in Diffusing Systems

In order to discern aggregation in solutions, we present a quantum mechanical analog of the photon statistics from fluorescent molecules diffusing through a focused beam. A generating functional is developed to fully describe the experimental physical system as well as the statistics. Histograms of the measured time delay between photon counts are fit by an analytical solution describing the static as well as diffusing regimes. To determine empirical fitting parameters, fluorescence correlation spectroscopy is used in parallel to the photon counting. For expedient analysis, we find that the distribution's deviation from a single Poisson shows a difference between two single fluor moments or a double fluor aggregate of the same total intensities. Initial studies were performed on fixed-state aggregates limited to dimerization. However preliminary results on reactive species suggest that the method can be used to characterize any aggregating system.Comment: 30 pages, 5 figure